This invention relates to a flame deflecting device for mounting on a building exterior.
A flame deflector was described by T. Z. Harmathy in an earlier U.S. Pat. No. 3,968,841. The justification for using flame deflectors on building exteriors was discussed at length in that patent so that this disclosure will largely deal with the advantages of the new flame deflector designs over those in U.S. Pat. No. 3,968,841.
The essential part of the flame deflector of U.S. Pat. No. 3,968,841 is a panel, mounted in an upwardly extending position above those "openings" of the building envelope where flames or hot gases are capable of emerging if fire occurs. These openings are normally windows, and occasionally balcony doors. The panel is held in an upwardly extending position by a flame- or heat-destructible element. If fire emerges from the building through an opening, the destruction of that element allows the panel to assume an essentially horizontally-extending position, thereby protecting the storeys above from exposure to flames or radiated heat.
It was said that to provide effective protection, the panel must be at least 3 feet (approx. 0.9 m) wide, preferably 4 ft (approx. 1.2 m) or more. Since the panels are mounted upwardly along the facade, accommodating them may present some difficulties for buildings built with vertical distances of less than 1.0 m between the openings. Unfortunately, these are the buildings most susceptible to the spread of fire from storey to storey along their facade, and therefore require special protection.
A new type of flame deflector has been designed for use where there is a need to provide protection against the external spread of fire in those buildings where the openings (usually windows) are closely spaced in the vertical direction.